Answers (1)
Did you know that 'essential' is the adjective form of 'essence'? So the answer to your question is "by definition". But what is the essence of the human person? We will come back to that question.
What is 'philosophy'? The word is Greek for "worldly wisdom", but the field has always been remarkably devoid of wisdom. If you hang out with philosophers, you soon notice that they use a lot of big words, those words have meaning only within the subject of philosophy, they mostly quote opinions of other philosophers, and they almost never cite actual facts to support anything they say. They only compare the pronouncements of one philosopher to the pronouncements of another. If you point out that they have not actually said anything, they will shout insults at you and physically eject you from their presence.
So how does this expose "the essence of the human person?" Well, the human person is a pack animal, like wolves, and every human desperately wants to be accepted by his peers. Being right does not matter much unless his peers pride themselves on being right. (That applies to carpenters and ditch diggers and people doing measurable things.) So he learns to entertain his fellows by quoting their heroes without ever saying anything that leads to a contest of any kind. Nietzsche laid an egg when he announced "God is dead," but that only offended outsiders, so it is still accepted but not discussed much.
There you have "the essence of the human person" explained through philosophy, but you can't discuss it with any philosopher.